The present invention relates to exercise equipment, and more particularly, to an exercise machine for simulating a stepping motion, wherein the horizontal component of the stepping motion for each foot may be in a side-by-side parallel orientation or an opposed orientation.
The prior art includes a number of mechanisms for simulating stepping or stair climbing activities. Specifically, U.S. Pat. No. 5,139,470 discloses an exerciser having a pair of treadles pivotally coupled to a frame, wherein each treadle is associated with a hydraulic cylinder and each cylinder is coupled to a valve to provide control of the hydraulic fluid between the cylinders so that the resistance of the cylinders may be varied, thereby adjusting the relative resistance to motion of the treadles.
U.S. Pat. No. 3,756,595 discloses a leg exercising device for simulating ice skating. The ice skating simulator provides motion of the feet to define either a linear path, or alternatively a curvilinear path.
U.S. Pat. No. 3,598,404 discloses a calf exercising apparatus having a pair of independently adjustable inclined platforms, wherein the platforms are interconnected by a central bearing point.